Trestle-jack.



0. NELSON. TRESTLE JAGK. APPLICATION FILED APR 8, 1910.

1,002,741, Patented Sept.5,1911.

2 1 1. 4 5 J2 I 7 L 1 11 OLOF NELSON, OF CHICAGO, ILLINOIS.

TRESTLE-JACK.

Specification of Letters Patent.

Patented Sept. 5, 1911.

Application filed April 8, 1910. Serial No. 554,189.

To all whom it may concern:

Be it known that I, OLOF NnLsoN, a cit-izen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Trestle-Jacks, of which the following is a specification.

My invention relates to improvements in adjustable trestle jacks, and has for one of its objects to provide in an adjustable trestle jack, lifting screws, that are longitudinally shiftable upon the beam of the trestle, or jack.

Another object of my invention is to provide, in a device of the character described, a structure which is readily and easily knocked down, for the purpose of contracting the space in which the device may be contained, as when the device is used in automobile service, the parts may be disassembled and packed in a bundle, or placed in a receptacle, occupying relatively very small dimensions.

Another object is to generally cheapen the cost of construction of such devices, to strengthen without adding materially to the weight, and to render such device gen erally adaptable and useful for the purpose for which they are intended.

Other and further objects of my inven tion will become apparent to persons skilled in the art from a consideration of the following description taken in conjunction with the drawing, wherein Figure 1 is a broken-away elevation of the device; Fig. 2 is an end view of the same; Fig. 3 is a section taken on line 3-3 of Fig. 1; Fig. 4 is a fragment of a leg, and a fragment of one of the spacing pieces, in section; and Fig. 5 is an enlarged section taken on line 5-5 of Fig. 1.

In all of the views, the same reference characters indicate similar parts.

10 indicates generally the horizontal composite beam or girder, made up of two parallel channel irons, 11 and 12, turned with their grooved sides confronting. Distance spacers, 13 and 14, are adapted to be inserted in the respective grooves of the channel irons, 11 and 12, one at each end, to maintain them in positive spaced relation. Bolts, 15, take through the channel irons, 11 and 12, and the distance spacers, 13 and 14. The bolts 15 are held in place by the nuts, 16, while the bolts hold the parts in relatively fixed, spaced relation. The bolts are readily removable when the nuts are taken therefrom. The legs, 17, of which there are preferably four, are removably attached to the distance spacers, 13 and 14, as by screw threads, as clearly shown in Fig. 4. Rectangular screw-threaded nuts, such as 18, are placed in the grooves afforded between the bars, 11 and 12, and are longitudinally shiftable therein so that they may be placed at any selected longitudinal points within the extent of the composite beam formed by the channel bars.

Lifting screws, 19 and 20, have threaded engagement with the nuts, 18, the bolts pass ing through the separated space between the channel bars being free to move longitudinally thereof with their respective nuts. These screws are provided with convenient means on their ends for turning them, such as perforations, 21, made in their relatively flat and enlarged circular ends, 22. Screws, 19 and 20, may be turned by the insertion of a bar within the perforations, 21, if desired, or a wrench may be applied to the surface of the flat head, 22, for this purpose. The upper ends of the screws, 19 and 20, are provided with shoulders, as at 23, that freely pass through the perforations in clips, 24, and are headed over, as at 25, to prevent their removal. The heads being lower than the surface of the clip 24, when the clip is placed in contact with the surface of the object to be lifted, the screw can be turned independently of the clip, and by this means save marring or boring into the surface of the lifted object.

The adjustable lifting trestle may be placed under the axle of an automobile, or other vehicle, or other object, and the screws, 19 and 20, may be longitudinally shifted to convenient points on the beam of the trestle consistent with the configuration of the surface presented by the object to be lifted, and the screws, 19 and 20, may then be turned to lift the object to any extent within the longitudinal limits of the screws. The object may be lowered by turning the screws in the opposite direction, and the adjustable trestle may then be removed.

When it is desirable to transport the trestle, as when it is carried on an automobile, it may be disassembled by unscrewing the legs; removing the bolts, 15, and placing the relatively long parts of the device, then disassembled, in relatively parallel relation, in which condition the device may be contained parts, in the manner described, is of valuable importance.

In general use, one adjustable trestle takes the place of two jacks, and by the use of two trestles the entire automobile, or other vehicle, may be entirely lifted from the floor and maintained in this elevated position for any desired length of time. It forms a solid andreliable base, and its adjustable features, with reference to the relative longitudinal position of the screws on the beam or girder, render it adapted for many uses not herein mentioned.

- For the purpose of maximum strength, with minimum weight, I prefer to make the legs, 17, of gas pipe, but, of course, they may be made of solid metal, if desired, and other means of connection to the respective end pieces of the trestle may be employed without departure from the spirit and scope of the invention.

It will further be understood by persons skilled in the art that numerous other changes may be made in the details of construction and arrangement of the device, and yet be within the scope of my invention as defined by the following claims.

What I claim as new and desire to secure by Letters Patent of the United States, 1s-

1. In an adjustable knock-down trestle,

opposing channeled beam members, distance spacers between the beam members at their ends, bolts taking through both said beam members and said spacers respectively for binding said beams and spacers together, a plurality of suitable lifting screws, and supporting nuts therefor wholly within the channel provided by said beam members, said members providing at their inner confronting faces guideways for said nuts for longitudinal adjustment of said lifting screws relatively to each other.

2. In an adjustable knock-down trestle, opposing channel irons, distance spacers engaging therebetween at the ends of the opposing channels thereof, means for binding said channel irons and spacers together, a suitable lifting screw, and a supporting nut therefor of depth slightly less than the width of said opposing channels, to permit movements of the nut therein for longitudinal adjustment of the lifting screw, said nut located between opposing channels.

8. In an adjustable knock-down trestle, opposing beam members having longitudinal channels in their confronting faces, a rectangular nut of depth slightly less than the width of said channels for guided movement between said opposing channels, a lifting screw passing through said nut, distance spacers of substantially the depth and Width of said nut engaging in the channels at the ends of the beam members, bolts taking through said beam members and distance spacers to bind the same together, and suitable legs connected with the distance spacers to support said structure.

In testimony whereof I hereunto set my hand in the presence of two witnesses.

OLOF NELSON. In the presence of W. LINN ALLEN, MARY F. ALLEN.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C. 

